多重不变图象特征抽取器

提出一种光电混合图象特征抽取器。特征抽取器从Ｈｏｕｇｈ变换数据中实时地抽取满足图象移动、转动与尺度缩放多重不变性的９个图象几何特征量和不变矩特征量，模拟实验证实了９个特征量的多重不变性。     

谈精品开放课程建设与人才培养

我国经历十几年的精品课程建设后取得了一定的成就,精品开放课程建设又将进一步促进我国高等教育质量的提高.本文旨在强调精品开放课程建设与人才培养密不可分的有机联系,提出在精品开放课程建设中应注重学生自主式研究型学习,并以电磁学课程为例就课程教学方法改革提出了一些建议.呼吁精品开放课程建设以学生为本,强调精品开放课程建设与教学改革中理性的回归.     

Theoretical analysis of nanosecond crystallization kinetics of phase-change optical recording films

A theoretical investigation of nanosecond crystallization kinetics of the phase-change optical recording films is presented. An extended Kissinger equation for the square-root heating is derived, which properly describes the temperature evolution of the films by nanosecond laser heating. The extended Kissinger equation was used to explain our previous experimental results.     

GaAs半导体材料中双光子吸收光限幅与偏振方向的关系

理论分析了线偏振光波的偏振方向对ＧａＡｓ半导体双光子吸收的影响，实现了ＧａＡｓ半导体材料中不同偏振方向的双光子吸收限幅，提高了双光子吸收光限幅的性能。     

Theory of Z-scan technique using Gaussian-Bessel beams with a phase object

This paper reports the theoretical study of combining Z-scan technique with Gauss-Bessel (GB) beams beside a phase object (PO) to measure the third-order nonlinear susceptibility components.By using this method,the sign of refractive index which depends on the shape of the close aperture Z-scan curve can be easily determined.Meanwhile,the magnitude of nonlinear coefficients can also be deduced by theoretical fit.The proposed method is advantageous for high sensitivity and imposes a lower stress in the cases of fragile materials,since small pulse energy is enough for the measurement of nonlinear coefficients.Predictions of the models are compared with Gaussian Z-scan measurement and GB Z-scan measurement.By using GB beams with a PO,the sensitivity of Z-scan measurements is found to be a factor of over 60 times greater than for Gaussian beams and 2 times greater than for Gaussian-Bessel beams.     

OCB液晶显示的动态驱动特性

研究了强锚定边界条件下光学补偿弯曲排列(OCB)液晶的动态驱动特性。理论模拟计算了OCB液晶盒内液晶分子指向矢在给定电压情况下的分布规律,得到光线垂直入射时液晶盒相对透过率随交流电压有效值的变化曲线。实验测试液晶盒的电光特性,并给出测试液晶盒动态驱动条件下的响应时间及视角特性。     

富勒烯衍生物中的自散焦、自聚焦及其相互转化

用Z扫描方法研究了富勒烯有机铬衍生物fac- and mer- [bis (1,2-diphenylphosphino) ethane] (tricarbonyl) (η²-fullerene-C₆₀) chromium的非线性折射特性;用速率方程理论分析了激发态光学非线性材料非线性折射行为,以及大光强下高阶激发态折射度如何引起材料自散焦-自聚焦相互转化.计算出了转变光强.并数值模拟了不同光强下Z扫描实验曲线的变化过程.理论计算与实验符合得较好. 关键词： 自散焦 自聚焦 富勒烯衍生物 Z扫描     

反饱和吸收激发态非线性材料的Z扫描分析

本文用速率方程理论分析了激发志光学非线性材料非线性吸收和折射,通过数值模拟讨论了激发态和基态吸收截面、折射度相互关系等参数对非线性吸收和折射性质的影响。并从理论上分析了C₆₀甲苯溶液的Z扫描实验曲线,它具有强非线性吸收和弱非线性折射。     

Optical nonlinearity measurement of 4-（N-methyl,N-hydroxyethl）amino,4＇-nitroazobenzene using a transmittance technique with a phase object（T-PO） with top-hat beams at 600-nm wavelength

The transmittance technique with a phase object（T-PO）,for measuring optical nonlinear coefficients is proposed with a top-hat beam.The sensitivity of the T-PO with a top-hat beam is a factor of 4 greater than that with a Gaussian beam.The validity of this method is verified by measuring the nonlinearity of a well-characterized liquid,CS 2 at 532-nm wavelength.The ease of use of this method has been proved by measuring a new compound 4-（N-methyl,N-hydroxyethyl）amino,4＇-nitroazobenzene（ANAB） at 600-nm wavelength,indicating that this method can be extended to the measurement of optical nonlinearities in a wide-band spectrum.